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Did You Know?

Our blood is mostly made up of four components: plasma, red blood cells, white blood cells, and colorless blood cells called platelets. An instrument called a hematocrit (because it "judges" the blood) is used to separate a sample of blood into its components. The normal hematocrit for men is about 48%, for women about 38%. An abnormal proportion of red blood cells, either too many or too few, is a good early indicator of many diseases. So when you give blood as part of a physical exam, your hematocrit is one of the findings your doctor will often check.

Origin and Etymology of hematocrit

International Scientific Vocabulary hemat- + Greek kritēs judge, from krinein to judge — more at certain